1. Field of the Invention
The present invention relates to a process of storing a solid chlorinating agent which tends to generate gases such as chlorine gas and nitrogen chloride gas upon decomposition during storage.
2. Brief Description of the Prior Art
Solid chlorinating agents have been widely employed commercially in various fields as disinfectants, germicides, bleaching agents and the like. Such solid chlorinating agents include trichlorinated and dichlorinated isocyanuric acid, anhydrides and hydrates of sodium and potassium dichlorinated isocyanurate and a mixture thereof and a composition thereof with auxiliary agents. These agents have been used in various forms such as powders, granules, grains and tablets.
These solid chlorinating agents are usually stored and transported in closed packing containers such as paper bags, plastic containers and metallic cans. Since the solid chlorinating agents will often be stored for a period of time of as long as one or two years after manufacture before they are actually used on site, noxious gases will be generated during storage upon decomposition of the solid chlorinating agents and those gases may exert undesirable influences, causing in rare cases dangerous incidents. For example, such noxious gases may causes label information on a container to become unclear or fade away completely. The gas generation also may cause the corrosion of packing materials or the breakdown of containers themselves from an increase in internal pressure therein. The gases may give off offensive odors to users or an unpleasant feeling upon opening of a packing container anywhere or during use on the site. Further, the gases generated by decomposition of the solid chlorinating agents are noxious and hazardous to the human body.
Accordingly, many attempts have been made so far to overcome those difficulties and disadvantages involved in the generation of the noxious gases. One attempt is to decrease the water content in the product, thereby preventing the generation of the gases upon decomposition during storage. However, it is almost practically impossible to industrially manufacture products virtually free of water. It also has been attempted to store the product under an atmosphere where outside moisture is completely blocked. For this purpose, where containers composed of a metallic material capable of blocking the outside moisture are used, the metallic material may be subject to corrosion or transformation and even broken during long periods of storage by the accumulation of the decomposed gases. A further attempt also has been made to prepare the product in granular or tablet form thereby decreasing the specific surface area of the product and, as a consequence, preventing the generation of the gases. However, these methods are not satisfactory for storing over a long period of time. It also has been proposed that the solid chlorinating agents be coated with a film such as paraffin wax or polyvinyl alcohol. The effect of this coating is not extensive enough and is not desired for use in disinfecting pool water because the coating may provide the water with oily substances. The addition of desiccants such as potash alum to the solid chlorinating agents to form a composition also has been proposed; however, the effect is not satisfactory.
It further has been proposed that a stabilizer such as limonene be added to the solid chlorinating agent in order to prevent the decomposition of the agent. The effect of the addition of this stabilizer is not enough, and sometimes may even accelerate the generation of gases or cause a yellow coloring on the agent.